Weight distributing hitch and slide bracket assembly

ABSTRACT

A weight distributing and sway controlling hitch assembly for towing a trailer behind a vehicle includes a hitch bar for mounting to a vehicle. The hitch assembly also includes a ball mount head carried on the hitch bar and a hitch connector carried on the ball mount head. A pair of friction pads are also provided for mounting on the trailer. Additionally, the hitch assembly includes a pair of shoes, each of the shoes being received on one of the pair of friction pads while allowing relative sliding movement thereto. Still further, the hitch assembly includes a pair of spring bars for distributing trailer weight relative to the vehicle. Each of the spring bars includes a proximal end mounted to the ball mount head and a distal end for engaging one of the shoes.

This application claims the benefit of U.S. Provisional Application Ser.No. 60/018,670, filed May 30, 1996.

TECHNICAL FIELD

The present invention relates generally to the towing field and, moreparticularly, to a new and improved weight distributing hitch assemblyincorporating a novel spring bar and slide block or shoe arrangement fordistributing weight and controlling trailer sway.

BACKGROUND OF THE INVENTION

Hitch assemblies for more evenly distributing the tongue weight of atrailer over the front and rear axles of a towing vehicle are well knownin the art. A particularly advanced design of weight distributing hitchassembly is disclosed in the assignee's issued U.S. Pat. No. 5,375,872to Kass et al. entitled "Weight Distributing Hitch". This hitch assemblyincludes a hitch bar for receipt in a receiver mounted to the vehicleand a ball mount head for mounting on the hitch bar at a selected tiltangle. A pair of spring bars are mounted at their proximal end to theball mount head. The distal ends of these spring bars are connected bymeans of cooperating lift units and chains to the frame of the trailer.Such state of the art lift units are exemplified by Reese Products, Inc.product number 21160 incorporating a body that is mounted to the trailerframe, a chain hook with pivoting locking lever and a safety pin forsecuring the chain hook and lever in an operative position. As is knownin the art, the amount of leveling or load transfer to the front axle ofthe vehicle is adjusted by the selection of the tilt angle of the ballmount head and the engagement of different links of the chains with thechain hooks of the lift units.

While such an arrangement is effective for its intended purpose, itshould also be appreciated that the state of the art lift unitconnection between the spring bars and trailer frame provides little orno effective means of resisting or controlling trailer sway: that is,undesirable lateral movement of the trailer relative to the towingvehicle. In fact, such sway may arise as a result of a number of factorsoften encountered during towing operation including uneven, rough and/orwinding road conditions; gusty cross-wind weather conditions, uneventrailer loading conditions; and/or result from inherently incompatibletrailer and towing vehicle suspension characteristics. Accordingly, aneed is also identified for a weight distributing hitch assembly thatprovides some inherent control of trailer sway to maximize driverconfidence, comfort and control during towing.

SUMMARY OF THE INVENTION

Accordingly, it is a primary object of the present invention to providea weight distributing hitch assembly of an improved design overcomingthe above-described limitations and disadvantages of the prior art.

Another object of the present invention is to provide an improved weightdistributing hitch assembly incorporating a spring bar and slide blockor shoe arrangement which effectively provides both weight distributionand sway control so as to improve towing performance and overall drivercomfort.

Additional objects, advantages and other novel features of the inventionwill be set forth in part in the description that follows and in partwill become apparent to those skilled in the art upon examination of thefollowing or may be learned with the practice of the invention. Theobjects and advantages of the invention may be realized and obtained bymeans of the instrumentalities and combinations particularly pointed outin the appended claims.

To achieve the foregoing and other objects, and in accordance with thepurposes of the present invention as described herein, an improvedweight distributing hitch assembly is provided for towing a trailerbehind a vehicle. The weight distributing hitch assembly includes ahitch bar of a type known in the art for mounting to the towing vehicle.More specifically, the hitch bar includes a mounting post that isreceived in the receiver box of a hitch receiver that is secured to theframe of the towing vehicle in a known manner.

The weight distributing hitch assembly also includes a ball mount headfor mounting on the distal or head-receiving end of a hitch bar.Preferably, a hitch ball, also of a type well known in the art, iscarried on the ball mount head. Such a hitch ball is adapted for receiptin a cooperating trailer coupler socket of the trailer to be towedbehind the vehicle.

The weight distributing hitch assembly also includes a pair of frictionpads. These friction pads are mounted to opposing sides of the trailersuch as the outwardly directed faces of the two frame rails that form anA-frame trailer.

The weight distributing hitch assembly also includes a pair of springbars for distributing trailer weight relative to the vehicle. Morespecifically, each of the spring bars include a mounting trunnion at itsproximal end that allows the spring bar to be secured to the ball mounthead. Each spring bar also includes an inwardly projecting or transverselug adjacent a distal end.

Still further, the hitch assembly also includes a pair of slide blocksor shoes. One shoe is received on and mounted to the lug at the distalend of each spring bar. In operation, the shoes engage and slide alongthe friction pads carried on the trailer frame. Since each friction padis formed from a durable, high friction material, frictional resistanceto relative sliding movement of the shoes is provided. As a result,lateral movement of the trailer relative to the towing vehicle isresisted and, therefore, an effective anti-sway mechanism isadvantageously provided. It should be appreciated, however, that thisfrictional resistance is readily overcome during operator controlledvehicle maneuvering so that relative pivotal movement about the hitchball and coupler socket is freely allowed during turning. Thus, trailersway is resisted without compromising any operator control.

Preferably each shoe includes a retaining bracket and cooperatingfasteners that are utilized to secure the shoe to the lug of theassociated spring bar. In addition, each shoe includes a channeldefining a load bearing face that engages one of the friction pads. Thechannel further includes side walls that lap the engaged friction padand maintain proper alignment between the engaged friction pad and theshoe during towing.

Still other objects of the present invention will become apparent tothose skilled in this art from the following description wherein thereis shown and described a preferred embodiment of this invention, simplyby way of illustration of one of the modes best suited to carry out theinvention. As it will be realized, the invention is capable of otherdifferent embodiments and its several details are capable ofmodification in various, obvious aspects all without departing from theinvention. Accordingly, the drawings and descriptions will be regardedas illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWING

The accompanying drawing incorporated in and forming a part of thespecification, illustrates several aspects of the present invention andtogether with the description serves to explain the principles of theinvention. In the drawing:

FIG. 1 is an exploded perspective view of the weight distributing hitchassembly of the present invention;

FIG. 2 is a detailed fragmentary and partially sectional view showingthe positioning of a spring bar with associated shoe for sliding along afriction pad carried on the trailer frame; and

FIG. 3 is a top plan view showing connection to a trailer.

Reference will now be made in detail to the present preferred embodimentof the invention, an example of which is illustrated in the accompanyingdrawing.

DETAILED DESCRIPTION OF THE INVENTION

Reference is now made to FIG. 1 showing the weight distributing hitchassembly 10 of the present invention. As should be appreciated, thehitch assembly 10 includes a hitch bar 12 of a type known in the artincluding a tubular mounting post 14 for engagement in a receiver box Rof a hitch receiver mounted to a vehicle (not shown). A pin P andcooperating clip C secure the hitch bar 12 in the receiver box R. Such ahitch receiver is, for example, a Class III 35 Series hitch receiver asmanufactured by Reese Products, Inc. of Elkhart, Indiana, the assigneeof the present invention.

The distal end of the hitch bar 12 includes a split end mounting rack 16having a series of aperture sets 18 allowing for height adjustment ofthe ball mount head 20. The ball mount head 20 may be a one-piece,integral construction cast from ductile iron. The ball mount head 20 issecured to the mounting rack 16 of the hitch bar 12 by means of twocooperating fasteners shown as bolts 22 and cooperating locking nuts 24.Washers 26 may be provided on the lower bolt 22 if desired.

More specifically the ball mount head 20 includes a pair of spaced,parallel mounting flanges 30 so as to form a yoke adapted to be receivedon the mounting rack 16. When properly mounted, the lower bolt 22extends through the aligned cooperating apertures 32 (only one visiblein FIG. 1) in the mounting flanges 30, the two washers 26 and the onealigned aperture set 18 in the interdisposed mounting rack 16.Similarly, upper bolt 22 extends through a pair of indexable, eccentricwasher 35, the aligned cooperating arcuate slots 34 in the mountingflanges 30 and through a second aligned aperture set 18 in theinterdisposed mounting rack 16. The arcuate slots 34 allow the ballmount head 20 to be pivoted relative to the hitch bar 12 about the lowerbolt 22. The locking nuts 24 are then placed upon the bolt 22 andtightened. This arrangement allows the tilt angle of the ball mount head20 to be selected by manipulation of the indexable, eccentric washers 35in a manner described in detail in previously referenced U.S. Pat. No.5,375,872 to Kass et al.

As also shown in FIG. 1, the weight distributing hitch assembly 10includes a pair of spring bars 36. Each spring bar 36 includes atrunnion 38 at its proximal end for mounting in the ball mount head 20.More specifically, each mounting trunnion 38 includes a pair ofoppositely disposed and outwardly projecting pivot pins 40. As is knownin the art, the pivot pins 40 are received in a first set of cooperatingsockets 42 in the upper and lower legs or platforms 44, 46 of the ballmount head 20. A more detailed presentation of the trunnion connectionof the spring bars 36 to the ball mount head 20 is presented in theassignee's U.S. Pat. No. 5,562,298, filed on Oct. 7, 1994, entitled"Weight Distributing Hitch Assembly", the disclosure of which is fullyincorporated herein by reference. Each spring bar 36 also includes a lug54 adjacent the distal end thereof that projects inwardly in atransverse direction. Thus, the lug 54 and main body of the spring bar36 form a substantially L-shape.

The upper platform 44 of the ball mount head 20 also includes anaperture for receiving a hitch connector such as hitch ball 52. Thehitch ball 52 is secured to the upper platform 44 by a weld or otherappropriate means known in the art.

A slide block or shoe 56 is secured to each lug 54. More specifically,each shoe 56 includes a pair of mounting posts 58 defining a lugreceiving slot 60 therebetween. As shown best in FIG. 2, the lug 54 ispositioned in the slot 60 and is held in position by an overlying clamp62 secured in place by a pair of fasteners such as screws 64 thatthreadedly engage in the mounting posts 58. Further, each lug 54includes a slightly flared or dimpled end 66 that prevents the lug frompulling free from the shoe 56 when clamped in position. Morespecifically, when the lug 54 is properly clamped in the shoe 56, theflared or dimpled end 66 prevents the lug 54 from pulling out of theshoe 56 back through the slot 60.

As best shown in FIG. 2, the shoe 56 on each spring bar 36 is receivedby and rides upon a friction pad 68. The friction pad 68 is formed froma durable, high friction material such as available from FrictionMaterial Company under products designation NA 104 which is bonded to asupporting substantially L-shaped mounting bracket 70 preferably formedfrom a sheet metal such as steel. Two countersunk screws 72 engage thebracket 70 and thereby secure the friction pad 68 and bracket to theframe. Fastener such as screws 74 or cooperating nuts and bolts (notshown) are utilized to secure the mounting brackets 70 to the frame F ofthe trailer when holes are not permitted in the top flange of the frame.

More specifically, as shown in FIG. 3, one friction pad 68 is mounted toeach frame rail F behind the trailer coupler socket S. In this position,each friction pad 68 is oriented to receive a shoe 56 or one of thespring bars 36. Spaced, parallel guide rails 76 (see FIG. 2) at theinner and outer margins of each shoe 56 form the sidewalls of a channel78 that insures that the shoes slide smoothly along and over thefriction pads 68 without binding. Each friction pad 68 resists freesliding movement of the shoe 56 riding thereon. Such sliding movementis, of course, generated whenever the trailer begins to sway in responseto, for example, rough, uneven and/or winding road conditions, gusts andcrosswinds and uneven trailer loading. At these and certain other timesthe frictional forces generated between the pads 68 and shoes 56 opposeor resist the lateral movement of the towed trailer relative to thetowing vehicle. Trailer sway is consequently reduced or virtuallyeliminated under substantially any anticipatable operating conditions.

It should be appreciated, however, that the degree of resistance totransverse movement is not great enough to interfere with the relativepivotal motion of the trailer about the hitch ball 52 and couplersockets that occurs as a result of driver input during normal vehicleoperation. Thus, the trailer still properly tracks behind the vehicleduring towing. Thus, it should be appreciated that sway control isadvantageously provided without any compromise of other importantoperating characteristics.

In use, the forward end of the trailer including the coupler sockets isinitially raised using the tongue jack J. The vehicle and trailer isthen positioned so that the hitch ball 52 underlies the coupler socketS. Using the tongue jack J, next the front end of the trailer is loweredso that the coupler socket S nests over the hitch ball 52. The couplerlatch is then closed to secure the trailer to the towing vehicle throughthe hitch assembly 10.

Next the front of the trailer and the rear of the tow vehicle are raisedabout 2-3 inches by operation of the tongue jack J. From this position,an individual may grasp an intermediate portion of the spring bar 36adjacent to the distal end thereof and flex the spring bar upwardly. Byshifting the spring bar 36 laterally once it clears the trailer framerails F, the spring bar may be released and the shoe 56 or channel 78dropped onto a friction pad 68. This is done so that the guide rails 76overlap the side edges of the friction pad 68 and the weight bearingsurface of the shoe 56 defined between the guide rails engages thefriction pad. As noted above, the guide rails 76 insure that the shoe 56remains in proper alignment as it slides relative to the pad 68.

The individual operator then positions the second spring bar 36 in thesame manner. The trailer tongue jack J is then retracted so that thehitch assembly 10 is distributing the full trailer tongue weight overthe front and rear axles of the towing vehicle in the desired manner.This is a simple and efficient operation that may be completed at theutmost convenience, confidence and satisfaction of the individual. Thereis no need to select a proper chain link or secure a lift bracket with asafety clip as required by the state of the art lift units commonlyutilized in this field.

Additionally, the present weight distributing hitch assembly 10 goes astep further than prior art weight distributing hitch assemblies byproviding control of trailer sway. Specifically, the friction pads 68provide sufficient resistance to the relative sliding movement of theshoes 56 to dampen swaying motion without actually interfering withproper pivotal movements of the trailer initiated by vehicle operatorinputs when turning during the towing operation. Accordingly, it shouldbe appreciated that the present invention represents a significantadvance in design that achieves more than the prior art weightdistributing hitch designs.

The foregoing description of a preferred embodiment of the invention hasbeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed. Obvious modifications or variations are possible in light ofthe above teachings. The embodiment was chosen and described to providethe best illustration of the principles of the invention and itspractical application to thereby enable one of ordinary skill in the artto utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated. All suchmodifications and variations are within the scope of the invention asdetermined by the appended claims when interpreted in accordance withthe breadth to which they are fairly, legally and equitably entitled.

We claim:
 1. A weight distributing and sway controlling hitch assemblyfor towing a trailer behind a vehicle, comprising:a hitch bar formounting to the vehicle; a ball mount head carried on the hitch bar; ahitch connector carried on the ball mount head; a pair of friction padsmounted on the trailer; a pair of shoes, each shoe of said pair of shoesbeing received on one of said friction pads while allowing relativesliding movement thereto; and a pair of spring bars for distributingtrailer weight relative to said vehicle, each of said spring barsincluding a proximal end mounted to said ball mount head and a distalend for engaging one of said pair of shoes.
 2. The hitch assembly setforth in claim 1, wherein each of said pair of shoes includes a channeldefining a load bearing surface for engaging one of said pair offriction pads, said channel further including sidewalls that lap saidengaged friction pad to maintain proper alignment between said engagedfriction pad and said engaging shoe.
 3. The hitch assembly set forth inclaim 1, wherein each of said pair of shoes includes a pair of mountingposts defining a lug receiving slot, a clamp and a fastener for securingsaid clamp to said mounting posts.
 4. The hitch assembly set forth inclaim 3, wherein said distal end of each of said pair of spring barsincludes a projecting lug.
 5. The hitch assembly set forth in claim 4,wherein said projecting lug includes a flared end.